Protective case for electric parts, and storage battery pack

ABSTRACT

A protective case for housing electric parts such as a storage battery ( 2 ) and a protective circuit ( 3 ). For example, the case comprises a body ( 1 A) and a lid ( 1 B). The body (IA) is formed integrally with a first terminal piece ( 4 ), which connects a terminal (30) of the protective circuit ( 3 ) with an external terminal ( 41 ) of the protective case. The lid ( 1 B) is formed integrally with a second terminal piece ( 21 ), which connects the terminal ( 30 ) of the protective case ( 3 ) with an external terminal ( 42 ) of the protective case.

TECHNICAL FIELD

The present invention relates to a protective casing for housing anelectric component and for providing electric conduction between theelectric component and an external object. It also relates to arechargeable battery pack using such a protective casing.

BACKGROUND ART

A prior-art rechargeable battery pack used for electric equipment suchas a mobile phone has such a structure as shown in FIGS. 5 and 6. Therechargeable battery pack 101 includes a casing body 101A and a lid101B. The casing body 101A is upwardly open and has a side wall 110formed with a through-hole 101 a. The lid 101B, which is capable ofclosing the upward opening 112 of the casing body 101A, is formed with aplurality of through-holes 111 a. The casing body 101A accommodatesrechargeable batteries 102 and a protective circuit board 103.

The protective circuit board 103 functions to prevent the rechargeablebatteries 102 from being overcharged. The protective circuit board 103is electrically connected to the rechargeable batteries 102. Theprotective circuit board 103 is formed with a plurality of terminals 130protruding from the surface thereof. When the protective circuit board103 is housed in the casing body 101A, the terminals 130 protrudeoutwardly from the casing body 101A via a through-hole 101 a.

The rechargeable battery pack 101 is provided with a plurality ofterminal segments 121 extending onto the upper surface of therechargeable batteries 102. Each of the terminal segments 121 has an end121 a electrically connected to a terminal 120 of a correspondingrechargeable battery 102 and the other end 121 b protruding outward fromthe lid 101B through a corresponding through-hole 111 a.

Thus, it is possible for the rechargeable batteries 102 to be chargedfrom the outside through the terminals 130 and to discharge (to supplypower) to the outside through the terminal segments 121.

The through-hole 110 a is designed to have a size sufficient for easilyreceiving a corresponding terminal 130. Each of the through-holes 111 ais designed to have a size sufficient for easily receiving the other end121 b of a corresponding terminal segment 121. Accordingly, a clearanceis formed around each of the terminals 130 and each of the other ends121 b of the terminal segments 121, which allows communication betweenthe inside and the outside of the casing body 101A. As a result,moisture and/or dust for example may enter from the outside via thethrough-holes 101 a, 111 a, which may cause a problem such as shortingin the protective circuit board 103.

To solve this problem, it may be considered that the surface of theprotective circuit board 103 may be coated with a resin for example forprotecting the protective circuit board 103. However, to perform such anadditional step decreases the production efficiency, increases the cost,and further, bars the weight reduction of the rechargeable battery pack101.

DISCLOSURE OF THE INVENTION

It is, therefore, an object of the present invention to positivelyprotect electric components such as rechargeable batteries and aprotective circuit board without increasing the cost.

In accordance with a first aspect of the present invention, there isprovided a protective casing for housing an electric component and forproviding electric conduction between the electric component and anexternal object, wherein the protective casing is integrally formed withterminal segments each of which has one end for electrical connection tothe electric component, each said terminal segment having another endfor electrical connection to the object.

The terminal segments integrated with the protective casing are utilizedas a means for providing conduction between the electric componenthoused in the protective casing and the external object. Unlike theprior art arrangement in which each terminal of an electric component isexternally exposed via a through-hole, the terminal segments provide anintegral structure together with the protective casing for electricalconnection to both the inside and the outside of the protective casing,thereby enhancing the hermetic ability of the protective casing againstentry of moisture or the like from the outside. As a result, it ispossible to reliably protect the electric component housed in theprotective casing from moisture, dust or the like.

The electric component to be housed in the protective casing may be acircuit board which carries semiconductor chips for example, or arechargeable battery.

According to a preferred embodiment, the protective casing comprises abox-like casing body which is formed by resin-molding to have anopening, and a resin lid for closing the opening, wherein at least oneof the casing body and the lid being insert-molded with the terminalsegments.

According to another preferred embodiment, said one end of each saidterminal segment is exposed or extended internally of the casing body,whereas said another end of said each terminal segment is exposed orextended externally of the casing body or the lid.

According to a further preferred embodiment, the terminal segmentsinclude a first terminal segment insert-molded with the casing body, anda second terminal segment insert-molded with the lid, wherein the firstterminal segment comes into contact with the second terminal segmentwhen the lid is mounted on the casing body to close the opening.

According to still another preferred embodiment, the second terminalsegment is pressed against a terminal of the electric component due toelastic restoration of the first terminal segment.

According an alternative preferred embodiment, the first terminalsegment is pressed against a terminal of the electric component due toelastic restoration of the second terminal segment.

According to a still further preferred embodiment, the first terminalsegment has a portion extending internally of the casing body, whereinsaid portion is convexly bent to have an apex for clamping the secondterminal segment between the apex and the terminal of the electriccomponent.

According to an alternative preferred embodiment, the second terminalsegment has a portion extending internally of the casing body, whereinsaid portion is convexly bent to have an apex for clamping the firstterminal segment between the apex and the terminal of the electriccomponent.

In accordance with a second aspect of the present invention, there isprovided a rechargeable battery pack comprising rechargeable batteries,a protective circuit board electrically connected to the rechargeablebatteries for protecting the rechargeable batteries, and a resin casingfor housing the batteries and the protection circuit board, wherein thecasing is insert-molded integrally with terminal segments which areelectrically connected to the protective circuit board and/or therechargeable batteries and are electrically connectable to an externalobject.

In this rechargeable battery pack, the terminal segments are integratedwith the casing by insert molding, and the rechargeable batteries andthe protective circuit board housed in the casing are electricallyconnected to the external object, so that the casing is not formed witha passageway for communication between the inside and the outside of thecasing, as opposed to the prior art. Therefore, moisture and dust areunlikely to enter the casing, and hence, it is unnecessary to coat theprotective circuit board with a resin for example to prevent shorting inthe protective circuit board. Further, since the terminal segments canbe mounted at the same time as resin-molding the casing, it is possibleto provide electric conduction between the inside and the outside of thecasing and to reliably protect the protective circuit board againstmoisture and dust without causing a decrease of the assembly efficiencyand an increase of the manufacturing cost.

According to a preferred embodiment, the protective casing comprises abox-like casing body which is formed by resin-molding to have anopening, and a resin lid for closing the opening, wherein at least oneof the casing body and the lid being insert-molded with the terminalsegments.

According to another preferred embodiment, said one end of each saidterminal segment is exposed or extended internally of the casing body,whereas said another end of said each terminal segment is exposed orextended externally of the casing body or the lid.

According to a further preferred embodiment, the terminal segmentsinclude a first terminal segment insert-molded with the casing body, anda second terminal segment insert-molded with the lid, wherein the firstterminal segment comes into contact with the second terminal segmentwhen the lid is mounted on the casing body to close the opening.

According to still another preferred embodiment, the second terminalsegment is pressed against a terminal of the electric component due toelastic restoration of the first terminal segment.

According an alternative preferred embodiment, the first terminalsegment is pressed against a terminal of the electric component due toelastic restoration of the second terminal segment.

According to a still further preferred embodiment, the first terminalsegment has a portion extending internally of the casing body, whereinsaid portion is convexly bent to have an apex for clamping the secondterminal segment between the apex and the terminal of the electriccomponent.

According to an alternative preferred embodiment, the second terminalsegment has a portion extending internally of the casing body, whereinsaid portion is convexly bent to have an apex for clamping the firstterminal segment between the apex and the terminal of the electriccomponent.

Various features and advantages of the present invention will beapparent from the detailed description of a preferred embodiment givenbelow with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an overall perspective view showing a rechargeable batterypack embodying the present invention.

FIG. 2 is an exploded perspective view of the rechargeable battery packshown in FIG. 1.

FIG. 3 is a sectional view taken along lines III—III in FIG. 1.

FIG. 4 is an enlarged sectional view illustrating a principal portion ofthe rechargeable battery pack shown in FIG. 1.

FIG. 5 is an exploded perspective view showing a prior-art rechargeablebattery pack.

FIG. 6 is a sectional view showing the prior-art rechargeable batterypack.

BEST MODE FOR CARRYING OUT THE INVENTION

The preferred embodiment of the present invention will be describedbelow with reference to FIGS. 1 through 4.

A rechargeable battery pack 1 generally comprises a casing body 1A madeof a resin, a lid 1B similarly made of a resin, rechargeable batteries 2housed in the casing body 1A, and a protective circuit board 3 forpreventing the rechargeable batteries 2 from being overcharged.

The casing body 1A, which may be formed by molding for example, has aconfiguration of a bottomed box which is upwardly open. The casing body1A has a side wall 10 provided with a plurality of first terminalsegments 4 each partially embedded by insert molding. Each of the firstterminal segments 4 has an end portion 4 a which is convexly bent toproject inwardly of the casing body 1A. The bent of each first terminalsegment 4 has an apex 4 c which is movable toward the side wall 10 ofthe casing body 1A. The other end 4 b of the first terminal segment 4 isexposed externally at the side wall 10 of the casing body 1A.

The lid 1B is formed, by molding, into a plate-like configuration toclose the upper opening 12 of the casing body 1A. The lid 1B is providedwith a plurality of second terminal segments 21 each partially embeddedby insert molding. Each of the second terminal segments 21 has an end 21a suspending from the lid 1B into the casing body 1A, whereas the otherend 21 b of each second terminal segment is exposed externally of thelid 1B.

Various electronic parts such as semiconductor chips and/or resistorsmay be mounted on the protective circuit board 3. The protective circuitboard 3 has an obverse surface provided with a plurality of terminals 30each of which is electrically connected with a respective electronicpart and a respective rechargeable battery 2. Each of the terminals 30may comprise a gold-plated electrode pad made of aluminum or copper forexample. The terminal 30 is electrically connected to a correspondingfirst terminal segment 4 and a corresponding second terminal segment 21.The rechargeable batteries 2 are housed on the reverse side of theprotective circuit board 3 in side-by-side relation to each other. Eachof the batteries 2 has a terminal 20 electrically connected to acorresponding terminal 30 via a wiring pattern formed on the protectivecircuit board 3.

The rechargeable battery pack 1 having the above structure may beobtained by placing the rechargeable batteries 2 and the protectivecircuit board 3 in the casing body 1A, and then closing the upperopening 12 of the casing body 1A with the lid 1B.

Specifically, as clearly shown in FIG. 4, the protective circuit board 3is housed in the casing body 1A so that each of the terminals 30 of theprotective circuit board 3 comes into contact with a corresponding firstterminal segment 4. Then, the rechargeable batteries 2 are housed inside-by-side relation to each other to be electrically connected to theprotective circuit board 3. At this time, since the apex 4 c of eachfirst terminal segment 4 is movable toward the side wall 10 of thecasing body 1A, it is possible to position the rechargeable batteries 2next to the protective circuit board 3 within the casing body 1A.

Then, the upper opening 12 of the casing body 1A is closed with the lid1B. At this time, the end 21 a of each second terminal segment 21suspending from the lid 1B is inserted, from above, between acorresponding terminal 30 of the protective circuit board 3 and acorresponding end 4 a of the first terminal segment 4 which areotherwise in contact with each other. Since the apex 4 c of the firstterminal segment 4 is movable toward the side wall 10 of the casing body1A, it is possible to easily insert the end 21 a of the second terminalsegment 21. The end 21 a of the second terminal segment 21 is clampeddue to the elastic restoration of the end 4 a of the first terminalsegment 4.

After the upper opening 12 of the casing body 1A is closed with the lid1B with the end 21 a of each second terminal segment 21 inserted, thecasing body 1A and the lid 1B are bonded together by a resin adhesive orby ultrasonic welding for example.

In this way, a rechargeable battery pack 1 is obtained in which the ends4 b of the first terminal segments 4 and the ends 21 b of the secondterminal segments 21 are exposed to the outside (See FIG. 1). Therechargeable batteries 2 of the battery pack 1 may be charged fromterminals 41 of an external charger, for example, through the ends 4 bof the first terminal segments 4. Further, it is possible to supplypower from the rechargeable batteries 2 to power supply terminals 42 ofa mobile phone for example, which is electrically connected to the ends21 b of the second terminal segments 21.

Since each of the first terminal segments 4 is partially embedded in thecasing body 1A while each of the second terminal segments 21 ispartially embedded in the lid 1B, it is possible to electrically connectthe inside of the casing body to the external parts without forming acommunication opening which was conventionally necessary. Further, dueto the insert-molding of the first terminal segments 4 and the secondterminal segments 21 together with the casing body 1A and the lid 1B,respectively, it is possible to prevent external moisture and/or dustfrom entering into the rechargeable pack 1 without adding any means forprotecting the rechargeable batteries 2 and the protective circuit board3 of the rechargeable battery pack 1.

Further, due to the prevention of moisture and/or dust entry into thecasing body 1A, the protective circuit board 3 does not need to becoated with a resin for example for prevention of shorting. In addition,the first terminal segments 4 and the second terminal segments 21 may beintegrated with the casing body 1A and the lid 1B, respectively, byinsert molding, so that protection of the protective circuit board 3does not result in a decrease of the production efficiency and anincrease of the cost.

On the other hand, since the end 21 a of each second terminal segment 21is kept pressed against a corresponding terminal 30 of the protectivecircuit board 3 at the apex 4 c of a corresponding first terminalsegment 4, it is possible to reliably maintain electric conductionbetween the second terminal segment 21, the first terminal segment 4,and the terminal 30. As a result, it is possible to positively preventcontact failure due to vibration for example.

In the embodiment described above, the protective casing or the casingcomprising the casing body 1A and the lid 1B accommodates therechargeable batteries 2 and the protective circuit board 3. However,other electric components may be housed instead of the rechargeablebatteries 2 and the protective circuit board 3.

Further, although both the first terminal segments 4 and the secondterminal segments 21 are provided in the above embodiment, only one kindof the segments may be provided.

In the above embodiment, since the end 4 a of each first terminalsegment 4 faces a corresponding terminal 30 of the protective circuitboard 3, that end 4 a of the first terminal segment 4 is convexly bentwhile the end 21 a of each second terminal segment 21 is made flat.However, in case where the end 21 a of each second terminal segment 21faces a corresponding terminal 30 of the protective circuit board 3,that end 21 a of the second terminal 21 may be convexly bent while theend 4 a of the first terminal segment 4 may be made flat.

What is claimed is:
 1. A protective casing for housing an electriccomponent and for providing electric conduction between the electriccomponent and an external object, the casing comprising: a box-shapedcasing body which is formed by resin-molding to have an opening, and aresin lid for closing the opening; wherein the casing body isinsert-molded with a first terminal segment which has one end forelectrical connection to the electric component, the first terminalsegment having another end for electrical connection to the object;wherein the lid is insert-molded with a second terminal segment whichhas one end for electrical connection to the electric component, thesecond terminal segment having another end for electrical connection tothe object; wherein said one end of the first terminal segment isextended internally of the protective casing, said another end of thefirst terminal segment being exposed externally of the casing body;wherein said one end of the second terminal segment is extendedinternally of the protective casing, said another end of the secondterminal segment being exposed externally of the lid; and wherein thefirst terminal segment comes into contact with the second terminalsegment when the lid is mounted on the casing body to close the opening.2. The protective casing according to claim 1, which comprises abox-shaped casing body which is formed by resin-molding to have anopening, and a resin lid for closing the opening, at least one of thecasing body and the lid being insert-molded with the terminal segments.3. The protective casing according to claim 2, wherein said one end ofeach said terminal segment is exposed or extended internally of thecasing body, said another end of said each terminal segment beingexposed or extended externally of the casing body or the lid.
 4. Theprotective casing according to claim 3, wherein the terminal segmentsinclude a first terminal segment insert-molded with the casing body, anda second terminal segment insert-molded with the lid, the first terminalsegment coming into contact with the second terminal segment when thelid is mounted on the casing body to close the opening.
 5. Theprotective casing according to claim 1, wherein the second terminalsegment is pressed against a terminal of the electric component due toelastic restoration of the first terminal segment.
 6. The protectivecasing according to claim 1, wherein the first terminal segment ispressed against a terminal of the electric component due to elasticrestoration of the second terminal segment.
 7. The protective casingaccording to claim 5, wherein the first terminal segment has a portionextending internally of the casing body, said portion being convexlybent to have an apex for clamping the second terminal segment betweenthe apex and the terminal of the electric component.
 8. The protectivecasing according to claim 6, wherein the second terminal segment has aportion extending internally of the casing body, said portion beingconvexly bent to have an apex for clamping the first terminal segmentbetween the apex and the terminal of the electric component.
 9. Arechargeable battery pack comprising rechargeable batteries, aprotective circuit board electrically connected to the rechargeablebatteries for protecting the rechargeable batteries, and a resin casingfor housing the batteries and the protective circuit board, wherein thecasing comprises a box-shaped casing body having an opening, and a lidfor closing the opening; wherein the casing body is insert-molded with afirst terminal segment which has one end for electrical connection tothe protective circuit board and/or a respective battery, the firstterminal segment having another end for electrical connection to theobject; wherein the lid is insert-molded with a second terminal segmentwhich has one end for electrical connection to the protection circuitboard and/or a respective battery, the second terminal segment havinganother end for electrical connection to the object; wherein said oneend of the first terminal segment is extended internally of the casing,said another end of the first terminal segment being exposed externallyof the casing body; wherein said one end of the second terminal segmentis extended internally of the casing, said another end of the secondterminal segment being exposed externally of the lid; and wherein thefirst terminal segment comes into contact with the second terminalsegment when the lid is mounted on the casing body to close the opening.10. The rechargeable battery pack according to claim 9, wherein thecasing comprises a box-shaped casing body having an opening, and a lidfor closing the opening.
 11. The rechargeable battery pack according toclaim 10, wherein each of the terminal segments has one end exposed orextended internally of the casing body, each said terminal segmenthaving another end exposed or extended externally of the casing body orthe lid.
 12. The rechargeable battery pack according to claim 11,wherein the terminal segments include a first terminal segmentinsert-molded with the casing body, and a second terminal segmentinsert-molded with the lid, the first terminal segment coming intocontact with the second terminal segment when the lid is mounted on thecasing body to close the opening.
 13. The rechargeable battery packaccording to claim 9, wherein the second terminal segment is pressedagainst a terminal of the electric component due to elastic restorationof the first terminal segment.
 14. The rechargeable battery packaccording to claim 9, wherein the first terminal segment is pressedagainst a terminal of the electric component due to elastic restorationof the second terminal segment.
 15. The rechargeable battery packaccording to claim 13, wherein the first terminal segment has a portionextending internally of the casing body, said portion being convexlybent to have an apex for clamping the second terminal segment betweenthe apex and the terminal of the electric component.
 16. Therechargeable battery pack according to claim 14, wherein the secondterminal segment has a portion extending internally of the casing body,said portion being convexly bent to have an apex for clamping the firstterminal segment between the apex and the terminal of the electriccomponent.